The treatment of chronic disease often requires repeated and prolonged access to a patient's vascular system to, e.g., to administer medications, blood products, nutrients and other fluids and/or to withdraw blood. When such procedures must be frequently repeated, it may be impractical and/or dangerous to insert and remove the catheter and the needle for each session. In this case, a semi-permanent catheter, (e.g., a peripherally inserted central catheter (PICC)), may be used. As would be understood by those skilled in the art, a PICC is a catheter that is inserted in a vein at a peripheral location, such as the arm or leg and threaded through the vein to the chest, in proximity to the heart.
To simplify the insertion process and reduce patient discomfort, PICCs and other semi-permanent catheters are generally made small and thin. Accordingly, their structural strength is limited by the thickness and type of material forming the catheter's walls. The amount of pressure and flow rate that the catheter can support without damage is also limited. If the maximum pressure the catheter can withstand (the burst pressure) or the maximum flow rate is exceeded, the catheter may be damaged or may completely fail possibly spilling fluids from the catheter into the body. During high pressure injections, escaping fluid may also damage the surrounding tissues.
Modern medical procedures rely considerably on visualization techniques to diagnose and treat diverse conditions. Some of these techniques include the injection of a contrast media to the vascular system to improve visualization of blood vessels and other biological structures during fluoroscopy, radiology, or other imaging. The contrast media is generally a liquid that is opaque to the visualization method used, so that body lumens containing the media appear distinct from other tissues. Typically, contrast media is introduced using a separate catheter designed to withstand the high injection pressures and flow rates necessary to disperse the media throughout the organs of interest. For example in the case of fluoroscopy, the contrast media may be a substance opaque to X-ray radiation. More modern visualization methods such as, for example, enhanced computed tomography (CT) may require the introduction of different contrast media, as would be understood by those skilled in the art.
Conventional PICC catheters are unable to withstand the high pressures and flow rates associated with the introduction of visualization media which are often substantially above what is used for the infusion of medications. Thus, it is often necessary to insert one or more additional catheters dedicated to the contrast media increasing patient discomfort and the time and costs associated with the procedure. If the patient exhibits poor peripheral venous access, the insertion of an additional contrast media catheter may be difficult.